No fission fragment occurs?

when i accord example “extended/hadronic/FisssionFragment” to produce fisssion fragment, it seems no fragment produce, to confirm the particle produced is fragment, the code below used:

if(G4IonTable::IsIon(step->GetTrack()->GetDefinition()))

to produce fission fragment, except according example “extended/hadronic/FisssionFragment”, something else shauld i do?

In your application, do you have Geant4 production cuts turned on? Often, fission fragments have a very short range, and production cuts will prevent them from being instantiated as tracks. If you turn off production cuts (or at least set the “proton” cut, which includes ion, to a small value), then you should see the fragments as tracks.

the cut value of my application is default, first i want to obtain the kinetic energy of fission fragment as thermal neutron bombing enriched Uranium, it seems not concerning the range of fission fragment, the key code below:

if(step->GetTrack()->GetDefinition()->IsGeneralIon())
G4double ede = step->GetPreStepPoint()->GetKineticEnergy();

the results indicate the kinetic energy is 0 MeV

Here, a macro for example Hadr03 (with Geant4 10.7), the printout and the plot of fission fragments.

siyuan.mac.txt (909 Bytes)
siyuan.out.txt (4.0 KB)

sorry, i used “siyuan.mac.txt” to run the application “Hadr3”, the results is not same with yours, here is key information:

Geant4 version Name: geant4-10-07-patch-01 [MT] (5-February-2021)

List of nuclear reactions:

              neutron + U235 --> N gamma or e- + 2 neutron:       5   Q =  9.7775 MeV
              neutron + U235 --> N gamma or e- + 3 neutron:       2   Q =  10.275 MeV
              neutron + U235 --> N gamma or e- + 5 neutron:       2   Q =   16.95 MeV
                neutron + U235 --> N gamma or e- + neutron:       1   Q =  8.7925 MeV

the results from you:

Geant4 version Name: geant4-10-07-ref-05 (31-May-2021)
List of nuclear reactions:

neutron + U235 → N gamma or e- + 2 neutron + Ba144 + Kr90: 1 Q = 181.22 MeV
neutron + U235 → N gamma or e- + 2 neutron + Nb103 + Sb131: 1 Q = 183.31 MeV
neutron + U235 → N gamma or e- + 3 neutron + Pr150 + As83: 1 Q = 177.9 MeV
neutron + U235 → N gamma or e- + 3 neutron + Sr94 + Xe139: 1 Q = 177.94 MeV
neutron + U235 → N gamma or e- + 4 neutron + Ba141 + Kr91: 1 Q = 170.99 MeV
neutron + U235 → N gamma or e- + 4 neutron + Cs138 + Rb94: 1 Q = 177.77 MeV
neutron + U235 → N gamma or e- + 4 neutron + La140 + Br92: 1 Q = 186.8 MeV
neutron + U235 → N gamma or e- + 4 neutron + Sr95 + Xe137: 1 Q = 177.08 MeV
neutron + U235 → N gamma or e- + 5 neutron + Ba144 + Kr87: 1 Q = 180.21 MeV
neutron + U235 → N gamma or e- + neutron + Cs141 + Rb94: 1 Q = 174.73 MeV

i do not kown what cause this huge difference, Geant4 version? my Geant4 is the latest version from official website.
siyuan.out.txt (67.5 KB)

It seems that, in your version, the command
/process/had/particle_hp/use_Wendt_fission_model is inefficient.

In Hadr03.cc, activate the line
G4ParticleHPManager::GetInstance()->SetUseWendtFissionModel(true);

@maire ,thanks!,now it works well.